I'm thinking the white barn was the hay/cow barn and the gray one was the tobacco barn. Tobacco barns are common in this part of Indiana. Most are disused, now that the tobacco industry has collapsed. Up through the 1990s, tobacco growing was an important source of income out here. It was labor intensive, but one acre of tobacco would net you $3000 - as opposed to the $300 an acre of corn would get you. No wonder people grew tobacco for so long.
Tobacco was tied in bundles and then hung across poles to cure in these barns. The high humidity of this area allowed for a slow cure. The barns were covered just enough to keep out the rain, but sided in a way to allow for a lot of air flow. You can really see through the gaps in this one.
Do a Google search for 'tobacco barn history' for some fascinating photos of structures like these.